Self-cocking firing mechanism



Jan. 26,1926. 1,570,677

C. J. JULSTEDT SELF COOKING FIRING MECHANISM Filed July 26. 1922 2 Sheets-Sheet '1 if www,

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c. J. JULSTEDT SELF COCKING FIRING MECHANISM Jam.,4 26 g 1925.

Filed July 26, 1922 2 Sheets-Sheei 2 .www

Patented Jan. 26, 1926.

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CLAS J. JULSTEDT, OF BETHLEHEIl/I. PENNSYLVANA. ASSIGNOR TO BETHLEHEM.'

STEEL COMPANY, GF BET-ILEHED'I, PENNSYLVANIA, A CORPORATION OF PENN- SYLVANIA.

SELF-COOKING FIRING MECI-IANISM.

Application lled July 26, 1922.

To all v2li/2.0m t may concern.'

Be it known that I, CLAS J. JULs'rED'r, a citizen of the United States, and residing at Bethlehem, Lehigh County, State of Pennsylvania, have invented certain new and useful Improvements in Self-Cooking Firing lvlechanisms, of which the following 1s a specification.

This invention relates to breech loading guns and particularly to firing mechanisms for @uns of the sliding breech block type. y One object of this invention is to provide a firing mechanism in the form of a selfcont-ained unit which is readily removable from the breech block, and readily replaceable in order to facilitate inspection, and repair. Another object is to provide a firing mechanism in which the resistance to the pull exerted on the firing lever is greatest at an intermediate point in the travel of the lever and decreases toward the end of its movement, so that only a slight pull on the lever is required at the instant of firing.

One form of the invention is illustrated in the accompanying drawings in which:

Fig. 1 is a vertical section through the breech end of a gun with the parts of the firing mechanism, in their normal or at rest position;

Fig. 2 is a similar View showing the positions which the parts of the mechanism occupy at the instant the hammer is released to strike the cartridge;

Fig. 3 illustrates the position which-the parts of the mechanism occupy an instant after the tiring pin has Struck the primer;

Fig. 4 is a section on the line 4 4 of Figure 1;

Fig. 5 is a rear elevation of the firing mechanism holder or frame removed from the breech block;

Fig. 6 is a plan view of the same;

Fig. 7 is a diagram showing the force required in pulling the tiring lever at each point in its angular travel;

Fig. 8 is a diagram showing the compression of the main spring in pounds for the various positions which it occupies in the tiring operation;

Fig. 9 is a fragment of a section on the line 9-9 of Figure 4 showing the means for retracting the hammer in its normal or at rest position;

Serial No. 577,677.

Fig. l0 is a similar section taken on the line 101O of Figure ll showing said means in the fired position; and

` Fig. 11 is a section on the line= 11 ure 10.

The' breech portion l() of the gun has a breech recess 12 in which the breech block 13 is slidably retained, and is cut away axially of the bore at 14 to allow the introduction of a projectile with its powder case and the ejection of the case after firing, in well known manner. rlhe breech block is also cut away at 1G for this purpose, the apertures 14 and 16 being in register when the breech block` is lowered. Any usual eX- tractor (not shown) may be used and any well known means for raising and lowering the block (or moving it to one side in the case of a horizontally movable block).

.The breech block has a central transverse recess or bore 1'? extending from the back of the block toward its front face, the bore being suiiiciently large to receive the hammer and tapering' at its forward end to a small firing pin opening 26 in the face of the block. The block also has a recess 18 extending upwardly from the bottom of the block and intersecting the central bore 17. rlhe recesses formed in the block do not, however, so weaken it that it does not solidly support the shell case during tiring.

A holder' for supporting the firing mechanism is shown in Figures 5 and 6, this holder comprising a casing 19 and side cover 20, the whole forming a boi; or frame, open at the ends, in which the firing mechanism is mounted. The casing 19 fits closely in the recess 1S in the breech block and for the purpose of removably securing it therein is provided with a flat leaf spring, secured to the end of which is a button 22 adapted to fit snugly within the rear end of the bore 17. The button and spring constitute a spring latch.

A hammer 23 is pivoted at 24 in the casing 19 and carries at its free end a firing pin 25which is adapted to protrude through the hole 26 to strike the primer in the cartridge case. A lever or operatmg arm 27 for the mechanism is pivoted in the frame at 28 and is provided with a recess t0 accommodate a sear 30 which is pivoted at 29 in such recess. The pivot pin 28 passes of Figthrough the recess in the lever and forms a stop for the shoulders 31 of the sear for the purpose of limitingA the motion of the sear relative to the firing lever, so that the sear Will rockl with the-leverywhen the latter is pulled. c

To the other end of the sear is pivoted one end of a telescoping rod 32, the oppositeend of which carries a trunnion 33 fitting 1n a recess 34 in the hammer. At each end of the rod is a shoulder 36, andbetween these shoulders the firing spring 37 is conned, the rod acting` as a guide to keep thecoiled spring from buckling on being compressed. The sear has a nose 38 which bears against a shoulder 39 'when the lever is pulled to r0- tate the hammer about itspivotal axis. The movement of the lever in a rearward direction is limited by a stop 19 on the frame vwhich engagea shoulder 40 onthe lever.

For'locking the lever against accidental operation and for assisting in partially'cocking the hammer to enable theoperator to remove the firing mechanism from the breech block, a safety locking lever `42 is provided. This lever is pivoted 'to the frame and when swung into the position shown in Figure 1. its nose 43 lies in the path of the shoulder 41 on thev firing lever so that the latter cannot be moved. The lock is held in either safe or firing position by the point of: a spring pressedV plunger 44 engaging either depression 45 in theframe.

In a recess in the hammer near the pivot is disposed a plunger 46 which is. constantly urged outward by a spring 47, but is prevented from being forced completely out of said recess by a pin 46 pocketed in a recess 46h bored' to intersect at right angles the aforementioned recess containing, the plunger 4G and in the same. axial plane. The face ofthe plunger is hollowed out at 48 to conform with the contour of the pin 46a with which it engages. The diameter of the pin 46 is less than the diameter ofits recess to allow thenecessary longitudinal movement of the plunger. The open end of the recess containing the pin 46a is closed by the inner face of the casing 19. Fixed in the casing `is a stop 49 which engages the pin 46a when the hammer is in its normal and fired positions;

The' normal position of the mechanism is as shownv in Figure 1. To operate the device; the safety catch is first set to fire po- '7 sition as in Figure 2. The leveris then pulled` through about 60'during which the :following successive movements take place. The spring 37 being slightly compressed in the at rest position of Figure 1, exerts initiallylva small forceon the sear, as indicated in Figure 8. Inasmuch as the shoulder 314 engages theprivot pin 28 the sear is rotatedlwith the lever, the springbeingfurther compressed, but only a slight'pull'being required (as shown graphically in Figure 7) until the nose of the sear engages'the shoulder 39. From this point on the hammer 1s rotated to the cocked position, and the spring compressed in this movement nearly to its solid. height, indicated by height cocked in Figure 8.

It will be noted that throughout the pull thus far, the direction of the force exerted .by the' spring onthe lever through the intermediary of the` sear is to the left of the pivot 28. At maximum compression the line of force passes through the pivot 28. Stop 19 engages the shoulder 40 to prevent furthermovementof the lever as soon as the line of force falls slightly to the right of the pivot 28. The spring now exerts a force on the sear tending to rotate it in a clockwise direction, and to thereby force the firing lever against the stop. Before the lever reaches the stop the are described by the sear nose falls outside that. described by the shoulder 89, the sear releases the hammer, and the spring forces the hammer sharply forward,

vthe firing pin being projectedthrough opening 26 in the front of the breech block to strike the-primer, the spring 47 being compressed by the fast moving hammer. Referring to Figures 3 and 8 it is seen that the line of action ofthe spring is now to the left of thepivot 28, and that the spring is still somewhat compressed. Hence, a force is exerted on the firing lever through the intermediary of the sear 3() which moves the lever to the right, resetting theY mechanism tothe position shown in Figure 1. DuringV this resetting movement the sear rocks on its pivot 29 and the nose 88 rides past the shoulder 39.

Then the lever has been returned to the extreme rightprsimultaneously with this movement, the spring 47 overcomes spring 37 so that the firing pinis. retracted slightly and will not project to foul the cartridge case when the breech block is lowered.

It has been noted that? the line of thrust of the spring approaches the pivot 28 as the. spring nears its maximum compression, and passes through the pivot when the spring is fully compressed. The parts are so designed that the maximum resistance to pull on the firing lever occurs materially before the maximum compression of the spring,.and as shown graphically in Figure 1s greatestY when the. iring'lever has completed about half its total angular movement. From this point on, the pulling force ,required decreases rapidly and is zero at the instant of firing. This is a material advantage, since a quick jerk on thelanyard develops sufficient momentum to complete the operation of firing, whereasfin the usual construction heretofore used, the maximum trigger pull occurs simultaneously with maximum spring compression and substantially at the instant of tiring, thus requiring a continually increasing pull on the firing lever.

When it is desired to remove the iiring mechanism from the breech block, the tiring lever is pulled until the shoulderll has passed the stop 19. The locking lever 42 is then swung to the position of Figure l and the trigger pulled until shoulder 40 engages the projection 43. At this point the hammer is almost fully cocked, `yet there is suicient clearance between the hammer and the spring 21 to allow the button 22 to be pressed forward releasing the iiring mechanism assembly to be withdrawn 'from the recess 18. Upon inserting the mechanism into the recess, the button 22 automatically snaps into position and locks the casing 19 in place.

To one skilled in the art the advantages of the invention will be apparent and it will be obvious that changes may be made in the design and arrangement of the elements of the mechanism to adapt the same for use with guns of various types, without departing from the scope and spirit of the invention.

' Having thus described the invention What is claimed as new and desired to be secured by Letters Patent is:

l. The combination with a breech block of the sliding type having a recess extending thereinto from one face, and a second recess extending thereintc from another face and opening into the first recess, of a frame, having a tiring mechanism mounted thereon, insertable into and removable from one of said recesses, said frame having also means to cooperate with the breech block to lock the frame in operat-ive position within the block, said locking means being accessible through the other of said recesses.

2. The combination with a breech block of the sliding type having a recess extending thereinto from one tace and a second recess extending thereinto from another face and opening into the first recess, of a frame, having a firing mechanism mounted thereon, insertable into and removable from one of said recesses, said frame having a spring latch to cooperate with the breech block in securing the frame in operative position within the block, said spring latch being accessible for manual operation through the other of said recesses.

3. In a breech loading gun, in combination, a breech block having a transverse bore, and an intersecting longitudinal recess, a frame containing a complete iiring mechanism inserted in the longitudinal recess, and a spring latch on the frame engaging the Wall of the transverse bore to hold the frame in place.

4. In a ring mechanism for guns, in combination, a tiring hammer, a tiring spring, and means for stressing the spring to operate the hammer, said means including an operating element, the spring and operating element being so mounted as to change their relative positions during the stressing operation, the resisting pressure ot the spring on the operating element decreasing as the stress in the spring increases.

5. In a tiring mechanism for guns, in combination, a tiring hammer, a coiled tiring spring, and means for stressing the spring to operate the hammer, said means including an operating element for axially compressing the spring, the spring and operating element being so mounted as to change their relative positions during the stressing operations, the resisting pressure of the spring on the operating element decreasing as the stress in the spring increases.

6. In a firing mechanism t'or guns, in combination, a tiring hammer, a coiled firing spring, and means for stressing the spring to operate the hammer, said means including a pivoted operating element for axially compressing the spring, the spring and operating element being so mounted as to change their relative positions during the stressing operation, the axis of the spring moving toward the aXis of rotation of the pivoted operating element as the spring is stressed, the resisting pressure of the spring on the operating element decreasing as the stress in the spring increases.

7. In a firing mechanism for guns in combination, a. hammer, a spring for operating the hammer, a pivoted operating element for cooking the hammer and stressing the spring, the operating element being adapted while stressing the spring to shift the line of action of the spring toward the pivot.

8. In a tiring mechanism for guns in combination, a hammer, a spring for operating the hammer, a pivoted operating element for cooking the hammer and stressing the spring, the operating element being adapt'- ed while stressing the 'spring to shiit't the line of action of the spring from one side ot the pivot to the other side thereof.

9. In a firing mechanism for guns in combination, a pivoted hammer, a pivoted operating elementI and a. spring interposed between the operating element and the hammer, the operating element being adapted to rotate the hammer against the action of the spring and subsequently to release the hammer for operation by the spring.

l0. In a tiring mechanism for guns in combination, a pivoted hammer, a pivoted operating element, and a firing spring interposed between the operating element and the hammer, the operating element being adapted to rotate the hammer against the action of the spring and. subsequently to release the hammer to be driven forward by the firing spring, ay stationary abutment and a spring disposed in the hammer and cooperating with the abutment to retract the hammer slightly after firing against the action of the firing spring.

11. In a. firing mechanism for guns in combination, a pivoted hammer, a firing spring, and a retracting spring, positioned to act on the hammer adjacent the pivotal axis thereof, the firing spring being adapted to act-nate the hammer to firing position and the r'etracting spring being adapted to retract the hammer after firing against the action of the firing spring.

12. In a firing mechanism for guns in combination, a pivoted hammer, means for actuating the hammer` to firing position, a stationary abutment, elastic means interposed between the hammer and the abutment, the abutment being adapted to stress the elastic means when the hammer isaetuated to firing position, and the elastic means being adapted to retract the hammer from tiring position. f 13. In a firing mechanism for guns in combination, a hammer, a firing spring and means for cooking the hammer against the action of the spring, for shifting the line of action of the 'spring whereby the hammer is released, the spring being adapted when the hammer is released to force the hammer forward and to change its line of action to reset the operating means.

14. In a firing mechanism for guns, in combination, a hammer, a pivoted firing lever, a firing spring, means on the firing lever adapted when the lever is actuated to cock the hammer against the spring, to cause the spring to exert a. force on the lever in the direction of its actuation and to release the hammer, and means for preventing movement of the firing lever under the action of said force, the spring being adapted after the release of the hammer to change the direction of its force on the firing lever to reset the latter.

15. In a firing mechanism for guns in combination, a hammer, a pivoted firing lever having two shoulders thereon, a firing spring interposed between the lever and the hammer, means on the lever adapted when the lever is actuated to cock the hammer against the action of the spring, cause the spring to exert a force on the lever in the direction of its actuation and to release the hammer and a safety lock adapted to cooperate with either of said shoulders to prevent initial movement of the trigger, or to prevent release of the hammer.

16. In a firing mechanism for guns in combination, a pivoted hammerhaving a recess therein and adapted to be actuated to ring position, and means for retracting the ham- ,mer from 'firingpositio-n comprising a stationary abutment, a member in the recess adapted to contact with the abutment, and

elastic meansL interposed between'said member and the hammer, the abutment being adapted to stress the elastic means when the hammer is actuated to firing position.

17.l In a firing mechanism for guns in combination, a hammer adapted to be actuated to v firing position and having a pair of mutually transverse recesses therein, and means for reti-acting the hammer from 'firing position comprising a plunger in one of said recesses, a spring adapted to urge the plunger outward, a pin in the other recess adapted to retain the plunger and to permit limited movement thereof, and a stop adapted to engage the pin to compress the spring when the hammer is fired.

18. In a firing mechanism for guns in combination,a hammer having a shoulder, a fulcrumed firing lever, a sear pivoted on the firing lever, a spring interposed between the hammer and the sear,and a toe extending from the sear and adapted to engage said shoulder when the firing lever is rotated.

19. In a liring mechanism` for guns in combination, a hammer having a shoulder, a fulcrumed firing lever, a sear pivoted on the firing lever, a spring interposed between the hammer and the sear, an abutment member which limits the pivotal movement of the'sear, and a toe extending from the Sear and adapted to engage said shoulder when the firing lever is rotated.

20. In a firing `mechanism for guns in combination, a hammer having a shoulder, a fulcrumed firing lever, a sear pivoted on the ring lever, a spring interposed between the hammer andthe sear, an abutment member normally engaging the sear to prevent the pivoted movement thereof, and a toe extending from the sear and adapted to engage 'said shoulder when the firing lever is rotated.

21. In a firing mechanism for guns in combination, a hammer having a shoulder, a fulcrumed firing lever, a Sear pivoted on the `tiring lever, a spring interposed between the hammer and the sear and adapted to be compressed by the rotation of the firing lever. an abutment member normally engaging the sear to prevent the pivotal movement thereof, and a toe extending from the sear and adapted to engage said shoulder when the firing lever is rotated to' compress the spring and to disengage said shoulder when the maximum compression of the spring is reached. l

In testimony whereof I hereunto aiiiX my signature.

' CLAS J. JULSTEDT. 

